Vehicles such as tractors often need to be attached to implements. The implements may be towed on their own wheels or may be mounted in a fixed manner to the rear of the chassis or frame of the tractor. The former include wagons, carts, material spreaders, mowers and the like. The latter include pavement breakers, backhoe attachments, grading blades, ground breakers and plows, among other devices.
These different implements are affixed to the vehicle in different ways depending upon the desired flexibility and rigidity of the coupling between them. For a relatively rigid connection, such as for implements like plows or cultivators that need to be raised and lowered with some regularity, the chassis of frame of the vehicle is coupled to a three-point hitch assembly, which often includes an adjuster such as an adjustable eye or a hydraulic actuator that permit the hitch to be raised and lowered with respect to the vehicle's chassis.
Other implements such as wagons and carts can be coupled to the tractor simply by providing a bracket (or “drawbar”) with a hole through which a pin can be inserted. These couplings are used to connect the tongues of wagons or other vehicles that do not need the vertical or lateral support of the rigid frame or chassis of the tractor.
These two couplings—the drawbar and the three-point hitch, are the generic couplings provided on most modern tractors. This is not to say, however, that the rear structures of the chassis or frame to which these are mounted are the same. Each tractor may be manufactured differently, and may have different and unique structures at the rear of the chassis or frame. Nonetheless, the vast majority include brackets or linkages affixed to the chassis or frame that provide the three point arrangement or have a drawbar receiving aperture.
Many tractors, due to the specialized uses for which they are sold, do not come equipped with a three-point hitch assembly mounted onto the chassis or frame. These tractors are often too small in practice to pull the kind of implements (plow, cultivator, etc) that are fixed to three point hitches. Furthermore, they are often bought with other specialized applications in mind that do not couple to a three point hitch. Examples include ditch digging attachments, backhoe attachments, pavement breaking attachments, pavement cutting attachments, road grading attachments and the like.
One difficulty with such vehicles is the lack of a standard hitching structure that a variety of these specialized attachments or implements can be fixed to. The traditional three point hitch is large and often unwieldy on such small tractors, and a simple means of towing the implement, while necessary, is not enough to support the implement.
Several systems for attaching an implement to a vehicle are worth mentioning.
U.S. Pat. No. 5,779,429 illustrates a system for quickly attaching an implement to a tractor. This device includes an elongated rectangular channel to which four hooks extend upward. The device is fixed to the tractor and the implement rests on the four upwardly extending hooks.
U.S. Pat. No. 3,876,092 illustrates an implement connecting coupler mechanism that is structured generally as a four bar linkage having one bar coupled to the frame of the tractor and the opposing bar of the linkage configured to be rapidly connected to an implement. A hydraulic cylinder is coupled to and extends between the two links to permit the implement link to be raised and lowered with respect to the tractor.
U.S. Pat. No. 3,912,092 is directed to a tractor lift, including a tubular framework that is coupled to the free ends of a three-point hitch A scoop-shaped enclosure is pivotally fixed to the bottom of this framework. The scoop-shaped enclosure has a lip along its upper edge that is hooked over the top of the framework.
U.S. Pat. No. 4,986,722 is directed to a mounting structure for a loading attachment. The structure includes two opposing tubular extensions at the bottom front ends of a pair of tractor loader arms and a shallow upwardly facing trough at the top of the ends of the loader arms. An implement, here shown as bucket, has an elongated tubular section that is sized to fit in the trough. The implement is supported by the trough. When the arms are lifted, the bucket pivots inward toward the tractor along its bottom edge and has horizontal slots that engage the two opposing tubular extensions extending from the bottom of the free ends of the loader arms.
U.S. Pat. No. 5,088,882 is directed to a universal coupling for coupling a front end working member, such as a bucket or other implement, to the ends of the loader lift arms of a tractor. The implement includes two downwardly opening hooks extending directly from the surface of the bucket and two lower more widely spaced-apart eyes. The hooks engage a short tubular member fixed to and extending between two vertically extending spaced apart plates. The plates are spread apart at their bases and define two slots therebetween for receiving the eyes of the bucket. There are holes in the plates for receiving laterally extending elongate members such as pins, bolts or the like that extend through the plates and through the eyes to hold them together. In this manner, the bucket or other implement is fixed to the ends of the vehicle's loader arms.
U.S. Pat. No. 5,403,144 is directed to a blade tilt assembly for a front end loader. The assembly includes a generally flat plate that extends laterally and vertically with respect to a skid steer vehicle. The plate has a laterally and horizontally extending top edge and a bottom edge that supports pins that can be extended downwardly. This plate is fixed to the ends of the vehicle's loader lift arms to couple a bucket to the skid steer vehicle. A rectangular metal frame is fixed to the back of the bucket, sized to receive the plate fixed to the loader lift arms. The frame includes a downwardly facing slot that receives the top edge of the plate. It also includes two vertically oriented holes that receive the two pins extending from the bottom of the plate. In this manner the top and the bottom of the plate are fixed to the ends of the loader lift arms.
U.S. Pat. No. 5,685,689 is directed to a quick attach system for a front end loader. It includes a blade for a front end loader that has horizontally extending tubular structures along its upper edge. The blade also has two eyes extending outward from and away from the rear of the blade. The loader arms have a framework that receives the blade. This framework includes an elongate tubular member to which are coupled two vertically extending members on each end. These vertically extending members have laterally extending trough-like structures that cradle the tubular structures to support the tubular structures and the blade to which they are coupled. The bottom of the vertically extending members supports slideable pins that engage the eyes on the blade.
U.S. Pat. No. 5,779,329 is directed to a mechanism allowing quick implement attachment to tractors. It includes a framework of a laterally extending rectangular tubular member that is fixed to two vertically extending members at each end of the tubular member. These vertically extending members have hooks at their upper ends and lower ends that face upward to receive laterally extending tubular structures of an implement. The framework is fixed to the ends of jointed arms that extend outward from the rear of a tractor and hold the implement to the ends of the arm. Latches extending across the open tops of the upper hooks hold the implement in place.
U.S. Pat. No. 6,422,805 is directed to a quick coupler for bucket excavators. It is directed to a latch for latching to a tubular structure, for example, a tubular structure on an implement.
U.S. Pat. No. 6,533,319 is directed to a ballast attachment for attaching a ballast to a rear three-point hitch of a tractor. A rod extends longitudinally between the two lower arms of a three-point hitch. A downwardly-facing notch or groove in a ballast receives the rod and rests upon it. In this manner the three-point hitch supports the ballast.
U.S. Patent Application Publication Number US2003/0005605 A1 is directed to a mounting plate for quick attachment bracket and bucket construction.
None of the foregoing references provide an adequate system for coupling directly to the frame or chassis of a tractor or other work vehicle to support an implement. Most disclose structures that are not attached directly to the frame or chassis of the vehicle to provide a mounting point for implements, but are attached to the implements themselves, such as couplings for attaching buckets to the end of implements such as loader arms already attached to the vehicle—they do not disclose a way of attaching the implement itself to the frame or chassis.
What is needed therefore is a hitching structure fixed to the rear of a tractor's frame or chassis for coupling an implement directly to the frame or chassis of the vehicle.
What is also needed is a structure that can be attached quickly and with a minimum of effort to the rear frame of a tractor and to a variety of implements.
What is also needed is a structure having surfaces that are readily couplable to a variety of implements.
It is an object of this invention to satisfy the foregoing needs by providing a system that, in one or more of its claimed embodiments, solves the problems described above. It should be recognized, however, that not every arrangement claimed below addresses all of the needs and provides all of the benefits identified above.